Screen Resolution from Command Line

[ldb88]

Is there a way to determine the current screen resolution from the command line? What about a way to change the resolution?

Thanks.

[i92guboj]

Is there a way to determine the current screen resolution from the command line? What about a way to change the resolution?

Thanks.

It depends on what you are speaking about.

If you mean related to the X graphics driver, you should be able to retrieve some info and make adjustments using xrandr.

[oz]

If you are talking about command line resolution, you can add the vga=xxx option to the kernel line in your /boot/grub/menu.lst file.

Here's a table with the different values you can use:

  FRAMEBUFFER RESOLUTION SETTINGS
     +-------------------------------------------------+
          | 640x480    800x600    1024x768    1280x1024
      ----+--------------------------------------------
      256 | 0x301=769  0x303=771  0x305=773   0x307=775
      32K | 0x310=784  0x313=787  0x316=790   0x319=793
      64K | 0x311=785  0x314=788  0x317=791   0x31A=794
      16M | 0x312=786  0x315=789  0x318=792   0x31B=795
     +-------------------------------------------------+

[ldb88]

It depends on what you are speaking about.

If you mean related to the X graphics driver, you should be able to retrieve some info and make adjustments using xrandr.

Thanks! Now my boss won't complain because he can't tell what's on the screen!

[ldb88]

Too late to edit, so I have to reply:

xrandr worked on Ubuntu with the nVidia drivers installed. But when I got to my computer at work (CentOS), it doesn't work anymore.

These are the commands I have tried:

xrandr -s 1280x1024
xrandr -display $DISPLAY -s 1280x1024
xrandr --screen Screen0 -s 1280x1024

None of them have worked.

[smolloy]

What were the error messages?

[i92guboj]

Different versions of xrandr can use different syntax, so, be sure you use xrandr -h and read the man page if available. Note also that the machine might be configured to use different video modes.

If your video card, monitor or driver doesn't support a given resolution, then it will not be available. The configuration of the Xorg server is also critical.

[ldb88]

There were no error messages. It just didn't do anything.

I'm pretty sure I am using the correct syntax, since I have read the man page for the version I am using.

The 1280x1024 is listed when I type xrandr -q so I assume it is supported.

Strange things are happening, though. When I go to System->Preferences->Screen Resolution and tell it to change, it doesn't change anything. It shows the message asking if I want to keep the new resolution, but nothing changed. When I go back and check to see what it has as my current resolution, it still says the old one.

[i92guboj]

Most problems about non-standard resolutions (those that are not 3:4, like the one you are trying to use) are often due to refresh rate settings.

Make sure that you are specifying correct horizontal and vertical refresh ranges in your xorg.conf. Take them from the manual for your monitor. Maybe you will also need to write a Modeline line for that concrete mode.